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Making a small fortune from a 2 stroke V8

Making a small fortune from a 2 stroke V8

Making a small fortune from a 2 stroke V8

(OP)

Here is my plan....Start with a large fortune, then make a large V-8 2 stroke for sportsman dragster racing.

The basic scheme is a supercharged piston port design with 4.840 bore spacing so I can use big block Chevrolet crank and rods.

The foggy areas for me at this point are port design, since the 2 stroke design software that I have looked into so far is not a good fit for bores in the range of 4.0".

I will also need to find a source for a piston with a ring on the bottom, I wonder, can a ring on the bottom piston be forged? It seems that it would be a big undercut.

Last thought is if the engine would require expansion chambers to make good power as they might be rather bulky I will have to model that to see once I have the approximate dimensions.

Any thoughts would be appriciated.

Jonathan T. Schmidt
http://www.motorsportsdesign.com

RE: Making a small fortune from a 2 stroke V8

Maybe you'd like to start with a model V8 plans and castings available on my site.

We have managed to get 3.2HP at 5000RPM.

Specification  1/2" bore, 3/4" stroke approx 1/6 scale.  Length 5 5/8", width 6 5/8", height 7/78" over air cleaner, 6 1/8" under bonnet.   Capacity 19.31cc - 1.178cu"   Idles around 800RPM.

Glenn.

www.metalbashatorium.com

RE: Making a small fortune from a 2 stroke V8

I suspect with enough money you could get pistons made with rings on the bottom, but even with a piston ported design I'm not sure why you need this.  Piston ported 2 strokes typically don't have a ring there.  

As to expansion chambers - YES you will need them to make the engine run well.  I have personally witnessed a person who took a well tuned 500 cc 2 stroke at about 105 hp, and turned it into a helpless pile of junk that could barely move the vehicle by simply removing the tuned pipe and replacing it with 4 stroke type exhaust.  A good place to start is Blair - Design and Simulation of Two Stroke Engines - available from SAE.  Be aware that good pipe design is only about a quarter science - the rest is sweat, hard work, and most importantly, innate ability granted by the Gods for the promise of the soul of your first born.

Good luck.

RE: Making a small fortune from a 2 stroke V8

500cc Grand Prix bikes are pushing near 200hp out of the 2-stroke engines.  When you say you are going to use a block of similar size to a BBC, I see a few potential problems.  You're going to have huge cylinders, 800-900cc's each.  This means you will have scavinging difficulties, especially at higher rpms.  In order to overcome the scavenging difficulties, you will need to have a very long stroke to give the cylinder plenty of time to scavenge.  In order to accomodate the long stroke, you would have to use a very tall deck block which is heavy, and the long stroke of the crankshaft will limit how many RPM's you can turn.  For naturally aspirated applications, you would have to seal a chamber underneath each cylinder in order to get the compression and vacuum needed to draw fuel into the engine and force it into the cylinders.  This would add weight and the crankshaft seals would create a lot of drag.  And, finally, for forced induction applications that do not move air through the crank case prior to it entering the cylinder will have to have a piston skirt longer than the stroke with a 2nd set of rings in order to keep the scavenge ports from becoming uncovered and supercharging the crankcase.

I hate to be so negative, but if you were to find a way around these problems, you could pull in a small fortune as you said, but not through racing.  Instead, I'd think companies like Detroit Diesel would be very interested.

RE: Making a small fortune from a 2 stroke V8

motorsportsdesign,

Well, if you've already got the large fortune, why don't you just bolt together two of these V-4s:

http://www.deltahawkengines.com/drawin00.htm

It's diesel, of course, but the rest is close. :)

Regards

RE: Making a small fortune from a 2 stroke V8

I thought Detroit Diesel made a large number of 2 stroke diesels in various capacities from 4 cyl to 14 cyl "V" configuration.

Also Johnson/Evinrude made a V8 2 stroke outboard motor some years ago. It might be down on capacity for your plans, but might be an easy starting point to prove or disprove some ideas.

Regards
pat

Please see FAQ731-376 for tips on how to make the best use of Eng-Tips Fora.

RE: Making a small fortune from a 2 stroke V8

Mercury makes a 2 stroke gas engine that is good for some 350hp, but it is a realativly low displacement engine, not like the one described earlier.  Formula 1 boats use 2 stroke engines, possibly v8's also.

There are plenty of large displacement 2-stroke diesels, but they are very limited on how fast they can turn.  Almost all 2-stroke diesels are forced induction of some sort and run RPM ranges from 100-2100, none of which will do you much good for racing.  The fact is that 2-strokes lose a great deal of efficience the faster they run.

RE: Making a small fortune from a 2 stroke V8

(OP)
Thanks all for the input,

I am planning to avoid the crankcase pumping style in favor of the roots blower scavenging. I have ssen many diesels with blowers but with valves in the head.

Thanks for the reminder about the Deltahawk engine, I had not looked at it for some time!

Best Regards

Jonathan T. Schmidt
http://www.motorsportsdesign.com

RE: Making a small fortune from a 2 stroke V8

I like Pat Primmers idea. Find an old GM 4-71 two stroke diesel. Replace the diesel fuel injector with a spark plug, and fit some EFI fuel injectors into the intake plenum around the cylinder bores somehow.

You are going to have to lower the compression a bit, but otherwise it should run o/k. A four cylinder distributor working at crankshaft speed might do the trick as well for both fuel and spark timing.

With a blower scavenged two stroke, you do not need to have the fancy pressure wave exhaust, with the expansion chambers and the very limited powerband it gives.

You could even two stage it with a turbo, just as they do on larger diesel trucks these days. It might actually breathe pretty well, especially if it has four exhaust valves per cylinder, and you overdrive the blower a bit.

It is going to be a pretty heavy engine though. I wonder if you could get an aluminium block cast? Hehe.

RE: Making a small fortune from a 2 stroke V8

(OP)
Warpspeed,

Thanks for the suggestion, casting blocks is not a big effort for me. I have made some very difficult tunnel ram intakes already.

I was planning to have piston port exhaust no valves in the head for simplicity. I am thinking that I will make billet heads like jet skis have.

Jonathan T. Schmidt
http://www.motorsportsdesign.com

RE: Making a small fortune from a 2 stroke V8

Valves in the head are going to give you the advantage of being able to alter exhaust timing quite independently of piston position. I think this would be a very great advantage for an experimental engine.

Another advantage is the piston temperature will be more even, if all the exhaust goes out through the cylinder head. Remember exhaust gas temperature is going to be far higher with gasoline, and a two stroke gasoline engine at that.

I think a standard Detroit Diesel might be a good starting point, mess around with it, then when you know a lot more, a custom block would give you an excellent opportunity to do some pretty amazing things.

RE: Making a small fortune from a 2 stroke V8

(OP)
I really prefer to have a valvless head, my goal is to make the engine as simple as possible, no cams pushrods valves etc.

These engine will likely be run an alcohal, I'm not sure what that will be like in a 2 stroke.

On the four stroke engines the heads are solid as no cooling is needed.

Jonathan T. Schmidt
http://www.motorsportsdesign.com

RE: Making a small fortune from a 2 stroke V8

Scott Mc,
The reason you want to have a ring at the bottom, is to keep the pressure from the intake ports from pressurizing the crankcase. Since at TDC the upper ring pack is above the intake ports. And since he is talking about a high positive pressure at the intake ports all the time. Unlike the naturally aspirated piston ported (as you say) design, which only has atmospheric or less at the inlet.

Using a Detroit diesel is a great idea.

RE: Making a small fortune from a 2 stroke V8

Cooper-Besmer and Ajax have 2-stk engines.  They only turn 300 RPM and have significantly larger displacement than a 500 cc moto-GP engine.  They maybe have a little more wieght than you want.  However the priciples of operation may help you out.  I think Ingersol-Rand makes a large gas compressor that is a 2-stk as well.

I was one of the people in college that thought 2-stks were only used in small, high rpm racing vehicles and outboard boats. ;)

If you happen to win the lottery, I can think of a few other projects to help you spend the money! ;)

RE: Making a small fortune from a 2 stroke V8

ever thought about using the coates spherical valve type head. go to the coates web site this could solve your problem

RE: Making a small fortune from a 2 stroke V8

"motorsportsdesign (Automotive) Jan 29, 2004
I really prefer to have a valvless head, my goal is to make the engine as simple as possible, no cams pushrods valves etc.

These engine will likely be run an alcohal, I'm not sure what that will be like in a 2 stroke.

On the four stroke engines the heads are solid as no cooling is needed.
Jonathan T. Schmidt"
 How about a head with an opposed piston  and twostroke style porting and air assisted injection  that can deliver alcohol fuel and nitros through the injector nozzle.
http://www.jack-brabham-engines.com/
Malbeare

A tidy mind not intelligent as it ignors the random opportunities of total chaos. Thats my excuse anyway
Malbeare

RE: Making a small fortune from a 2 stroke V8

(OP)
"ever thought about using the coates spherical valve type head. go to the coates web site this could solve your problem"

The Coates head will only solve problems for those that want more problems. In my opinion there is no commercial future for any engine that has components that have a shperical surface for sealing. The machining is too costly and the wear and rebuild situation would be impractical.

Jonathan T. Schmidt
http://www.schmidtmotorworks.com

RE: Making a small fortune from a 2 stroke V8

(OP)
Malbeare,

I took another look at your head, each time I look a little longer. I must tell you, I think you would be better served by a different name the six-stroke for marketing. Every time I hear it I think of some crazy cycle that has the piston making useless motion to air-out the cylinder.

How would you layout the head in a V12? The angle drive sounds too complicated, have you thought of any other schemes for cylinder rows of more than two cylinders?

I will give your design some more thought.

BTW, everytime I download the detailed animation from your site it is corrupt.

Jonathan T. Schmidt
http://www.schmidtmotorworks.com

RE: Making a small fortune from a 2 stroke V8

Jonathan T. Schmidt"

I have spoken to my webmaster about the corrupt file.
Our engine concept is a fourstroke principle. I named it a sixstroke as the upper piston completes two strokes while the main piston completes four strokes 4+2=6.The upper piston is a valving piston that returns some power to the main crank.The disks and or reeds augment the valving process but are not subject to cylinder pressures as the upper piston takes this.

what kind of V 12 are you looking at bore stroke capacity?
regards Malcolm Beare
 
http://www.jack-brabham-engines.com/

A tidy mind not intelligent as it ignors the random opportunities of total chaos. Thats my excuse anyway
Malbeare

RE: Making a small fortune from a 2 stroke V8

(OP)
I understand the concept of your cycle, I just think it deserves a more appealing name. Sorry I can't think of one at the moment. I think something that emphasises the elimination of the poppet valves or follow Otto and Brayton and call it the Beare Cycle.

I have been considering making a 5.0 bore spacing V-12 with proportions most similar to current after marker Big Block Chevrolets used in Sportsman level drag racing about 1.2 HP/CUIN.
Every time I get ready to go for it and start writing checks I get nervous and start thinking about things like 2-stroke V8s that might be less costly.

At the moment I am prototyping a carburetor and also doing some experiments with lost foam casting from machined styrofoam. Actually at this point, I am less concerned about the casting than accurate machining of the foam.

Jonathan T. Schmidt
http://www.schmidtmotorworks.com

RE: Making a small fortune from a 2 stroke V8

Jonathan T. Schmidt
Perhaps you could consider  a Beare sixstroke V4
Bore 4.500 stroke 4.250 upper bore 3.200 upper stroke 1.375
and then couple two for a V8 and three for a V12. then you would have a stand alone V4 at low production cost  or multiples for larger engines.
 malbeare
http://www.jack-brabham-engines.com/

A tidy mind not intelligent as it ignors the random opportunities of total chaos. Thats my excuse anyway
Malbeare

RE: Making a small fortune from a 2 stroke V8

Sorry Malbeare, your opposed piston is not unique.  Granted in your case it sounds like it is a modified valve, but there are other engines out there.  It seems to me, the crankshafts, pistons, con-rods and the supporting structure are the heaviest part of the engine.  Why do you want to double the weight of your engine?  In a stationary design, weight is not a problem, but in mobile aplications weight is everything.

Fairbanks Morse   http://www.fairbanksmorse.com/
here is the link to the brochure
http://www.fairbanksmorse.com/engines/literature/Opposed%20Piston%20Brochure.pdf

This manufacture has an oppsed piston, 2stk engine that dates back to 1930.  I have only heard of some of the engine information and am not an authority.  There was one located in the oil field as a generator about 50 miles from here.  If you are doing your own overhauls and maintenance on these engine, the double crankshaft design doubles your work.  Not to mention that you need to pull the top crankshaft to access the piston and liner, which is a common maintenance area in the stationary engine field.  Crankshaft timing is very critical, and they have twice the main and con-rod bearings as a normal engine.

For a link to natural gas fuel, pipeline compression engines, try this link:
http://www.coopercameron.com/cgi-bin/coopercompression/products/products.cfm?pageid=ccsbrands

Ajax and Cooper Bessemer are the 2stk engines for this company.

Dresser-Rand still makes a 2stk integral compressor for pipeline compression.

Ship engine builders use the 2stk design also, but I am not familer with that industry.

While these stationary engines are too big for a mobil aplication, they have been through many different types of designs.  Also, the are large enough engines that we can actually watch the combustion event happen with the correct equipment.

Good Luck,
dwedel



RE: Making a small fortune from a 2 stroke V8

(OP)
" Why do you want to double the weight of your engine?"

dwedel,

I think you question assumes facts not in evidence.

I remember a former employer that used to (rightly say to me;
"you haven't thought enough about your question to ask it"

I think that applies here.

Consider the weight in proporting to displacment and the mechanics reltive to the cycle changes.

 

Jonathan T. Schmidt
http://www.schmidtmotorworks.com

RE: Making a small fortune from a 2 stroke V8

"dwedel (Mechanical) Jan 16, 2005
Sorry Malbeare, your opposed piston is not unique."
The engines you refer to are supercharged two strokes not naturally aspirated fourstrokes.  The upper crankshaft is more akin to a cam shaft than a crank as it does not have a conrod but a very short stroke scotch yoke. The weight of the head is actually less than a standard fourstroke as there is less steel and more alluminium in the Beare sixstroke head.
We have done conceptual drawings of inline engines and there are at least three different methods of rotating the upper shafts or shaft in coordination with the main crank.We havent as yet done detailed finite analysis  of each concept so we dont know wich is most favourable or most acceptable to the market.
From a motorcycle point of view and small car point of view a V4 is the simplest as we still have access to 3 sides of every cylinder with a simple toothed belt  or chain drive from the upper, single shaft per bank, to the main crank.
malbeare
http://www.jack-brabham-engines.com/

A tidy mind not intelligent as it ignors the random opportunities of total chaos. Thats my excuse anyway
Malbeare

RE: Making a small fortune from a 2 stroke V8

Motorsportdesign & Malbeare,

By the way, for sake of simplicity, please allow me to abbreviate Fairbanks-Morse as F-M.  Thanks.

I have now explored Malbaere’s website.  And yes, my assumptions are suspect.

In regards to Motorsportdesign initial specs and comments:

Simple design for racing application
-no valves in head
-pressurized intake manifold
-2stk, v8 configuration
-machining a spherical sealing surface is too complex
-component life is relatively short (no million mile overhauls)

Are you planning on individual heads for each cylinder?  Large 2stks use this time saver.  Even ones with fuel valves/injectors in the head.

This is a simple supercharged two stroke engine.  My thought on your plan Motorsportdesign, is that your 2stk idea/design is sound.  People have done the same thing many times over, in many different applications.  I would expect that your 4stk design would work also.

Is your proposed market able to support either your 4stk or 2stk engine?  Most of the people in the racing circles like to tinker themselves, and making their own engine, allows them to do that.  How many people buy factory stock engines and race them?  Do the people who have the factory engines prefer the tested designs that Chevy, Ford, et. al. have?  Would they be willing to risk running a startup company’s engine.  Those are the questions I have, when I hear your proposal.  {shrug}

My observation is that most people don't make or lose money on the quality of the design, as much as a lack of marketing and buisness ability.  As I am an engineer and not a buisness major, I won't give you advice in this area.

In regards to Malbeare’s engine:

I assumed the bore for the upper cylinder was the same as the bore for the lower cylinder.  This is my main mistake.  With the upper cylinder roughly half the area of the lower cylinder you have half the force on the upper piston and driving components.  Thus you don’t have the weight of the F-M upper drive train.

The F-M upper piston was used to make a small amount of power; which the Beare engine probably doesn’t do.  My guess is the peak firing pressure on the upper piston creates more friction on the scotch yoke at that point and the possible power gain is negated.  This would be hard to measure, but is probably moot anyway.

How has the loss of work due to the upper piston expanding during the power cycle worked out?
How well has the scotch yoke survived sliding during the peak firing pressure event?
Did you weigh the Ducati Desmo heads, intake runners, and throttle bodies?
How about the Beare head parts, reed valves and throttle bodies that went on the Ducati engine?
How do you maintain an oil film on a scotch yoke bearing?
How do deal with the oil pooling on the top of the upper piston?
From your pictures of the exhaust disk, is that the exhaust port that is shown right below the upper crankshaft?  
Why is it so much smaller than your air intake system?  
Or is this just perception from the pictures?
Why do you have two intake manifolds, when most ported cylinders only use one?
Can you/have you taken a pressure trace of the engine during operation?  How does it compare to your predicted values?
What do you think of the fact that you have 3 seperatly unique sealing surfaces in your process, while the poppet valve has one type of sealing surface? (maybe two if you count the different temperatures of the intake and exhaust valves)

I suppose these questions are considered hijacking this thread.

I don’t know gentlemen, maybe Beare's head is a good alternative to poppet valves.  I lean towards the not side, but we’ll see what happens in about 40 years.  I read somewhere that Lord Kelvin said that people could never travel faster than 60 miles per hour.  If I miss my prediction here, at least others have made inaccurate predictions as well. I certainly don’t place my intellect on the same level as Kelvin’s, so I will probably guess wrong more than he did.  Maybe I can do as well as a meteorologist.

Good Luck

RE: Making a small fortune from a 2 stroke V8

The really hard part is to change the rules so they would let you race something different (god forbid).

RE: Making a small fortune from a 2 stroke V8

(OP)
yoyo you are right about racing rules driving out originality. I have nearly lost my interest in racing as it has become more of a celebrity sport than a technology sport.

Jonathan T. Schmidt
http://www.schmidtmotorworks.com

RE: Making a small fortune from a 2 stroke V8

malbeare,

 Race sanctioning bodies can be extremely finicky. Just ask your namesake, Mr. Brabham, how far the Brabham BT46 F1 car got back in 1978(?).



Once it demonstrated it had a significant advantage, even though it qualified within the existing rules, it was quickly "outlawed".

Regards,
Terry

RE: Making a small fortune from a 2 stroke V8

Is that a dustbin lid?

Not a nice car to follow apparently, as it sucked all the debris off the track and threw it out the back.

RE: Making a small fortune from a 2 stroke V8

scottmc
im needing to find a place that will roll  me a pipe
according to my specs.someone to roll the cones or just build the pipe altogether.

popwarlick(mechanical)

RE: Making a small fortune from a 2 stroke V8

popwarlick,
a specialist motorcycle exhaust maker REBAND in Australia
I get work done there
Phone 61 885 645122 ask for Rick.

A tidy mind not intelligent as it ignors the random opportunities of total chaos. Thats my excuse anyway
Malbeare

RE: Making a small fortune from a 2 stroke V8

Motorsportsdesign, concerning the use of the same crank as the chevrolet big block. Going from 4 stroke to 2 stroke is only possible with an odd number cylinder blocks. You could use the same crank but would get nice reciprocating and rotating dynamic moments resulting in vibrations. These moments are also the premice to internal efforts you clearly don't need because you'd have to beef up your block for strenght and since your talking about a racing engine, nothing you want to beef up...

Keep up the 2 stroke! God I love those

RE: Making a small fortune from a 2 stroke V8

Jonathan,

I was thinking about building a 2-str from a common small 4-cyl turbo-diesel 4-st when I realised what sledneck just pointed out-- having two combustions at the same time will be a problem which means a custom crank (which suddenly makes things a lot more expensive!)

Check out the 2-str Wilksch aero diesels: www.wilksch.com

cheers, derek

Join us at http://groups.yahoo.com/group/opensourcecars

RE: Making a small fortune from a 2 stroke V8

Back in the 70s there was a little Italian furniture manufacture.  His dream was to make a competitive motorcycle for road racing.  He made two sizes, 50cc and 125cc.  If memory serves me the 125 put out 47 hp at 8,000 RPM.  A sample bike made it to the states for an evaluation by one of the cycle magazines.  Never heard anything more about it.

The name was (Morbidelli)  I don't think the spelling is correct.  It would seem that if you could approach that output from a ported engine that is naturally asphirated you would do well.

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